Hobbyists who enjoy operating powered models realize the importance of maintaining control over the models during operation. Control may be accomplished by a cable directly connected to the model, or by radio signals transmitted from a remote control transmitter, usually hand-held, to a receiver mounted in the model.
A control failure may be due to operator error, or due to a part failure, but in either case, expensive damage to the model craft may result. Control failures due to a part failure can be overcome by improving the reliability of parts when the causes of failure become apparent.
The use of a wheel or arm member coupled to a servo-motor for transferring control motion from the servo-motor to control members is well known. Present known servo-wheels are formed of a synthetic material such as a plastic or the like. These wheels are coupled to either cables or metal control rods and also to servo-output shafts.
During controlled maneuvers these wheels are subjected to high stresses, often suddenly applied, and often rapidly repeated in reversed directions. As a result, a great deal of flex and wear, and sometimes failure, is imposed on the plastic part. This wear is cumulative, and over time the plastic wheel to metal control rod coupling becomes loose, creating slop or lost motion between the output shaft of the servo-motor and the control rods connected to the servo-wheel.
One prime area of such wear is at the spline connection between the present plastic wheel and the plastic servo-output shaft. Under certain conditions the plastic splines will spread, causing teeth to skip and misalign. Sometimes the splines of the servo-output shaft are stripped by the plastic splines of the wheel.
Another prime area of such wear is in the linkage connection between the control rods, and their respective mounting holes formed in the plastic servo-wheel. Eventually, the mounting holes in the plastic part wear and spread causing a loose fit or connection with the control rods. As a result, slop or lost motion occurs at the connection between the wheel and the control rod.
A further prime area of concern is the flexing of the plastic servo-wheel or arm member as a result of the high, sudden stresses imposed thereon. These stresses can cause distortion and eventual failure.
The foregoing illustrates limitations of the known prior art. Thus, it is apparent that it would be advantageous to provide an alternative directed to overcoming one or more of the limitations as set forth above. Accordingly, a suitable alternative is provided including features and benefits more fully disclosed hereinafter.